How to change Default Controller in MVC application?

How to change Default Controller in MVC application?

This is the first process which needs to learn to work with MVC application. When we start MVC application by default it throws page not found error like below.

In this article we will learn, how to solve this problem.  This article assumes that you already have very little experience of MVC and its various sections.

The error is due to not set proper controller. OK, now have a look on Global.aspx page of MVC application. We will find below section in Global.aspx page.

public static void RegisterRoutes(RouteCollection routes)
        {
         routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
         routes.MapRoute("Default", // Route name
               
                    "{controller}/{action}/{id}",
                    // URL with parameters
               
                    new { controller = "Home", action = "Index", id = UrlParameter.Optional
                    } // Parameter defaults
           
                    );
 
        } 

If observed closely, we will find there is MapRoute() function which contents Default controller and the controller name is Home. Now, if we go and visit controller folder of application, we will not find any Home Controller (By default in new MVC project) into it.

And when application starts, it tries to invoke Home controller when it is not available. And that’s why it throws error.

Solution:

We can solve this problem in two ways.

1)      By adding Home Controller

2)      By changing Default Controller in Global.aspx page.

Add Home Controller

Here we will just add one Home controller in controller section. Like below.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
 
namespace MVC3.Controllers
{
    public class HomeController : Controller
    {
        //
        // GET: /Call/
        public ActionResult Index()
        {
            return View();
        }
    }
}

And within Home controller, Index Action is present .So no problem. This is the first solution.

Change Default controller in Global.aspx page

To do same, at first we will add one controller like below.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
 
namespace MVC3.Controllers
{
    public class TestController : Controller
    {
        //
        // GET: /Call/
        public ActionResult MyTest()
        {
            return View();
        }
        public ActionResult Index()
        {
            return View();
        }
    }
}

We have added Test Controller and we would like to invoke MyTest() action by default. Now, we have to change default controller setting in Global.aspx page

 
public static void RegisterRoutes(RouteCollection routes)
        {
          routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
          routes.MapRoute(        
"Default", // Route name
               
"{controller}/{action}/{id}",
// URL with parameters
               
new { controller = "Test", action = "MyTest", id = UrlParameter.Optional
} // Parameter defaults
           
);
 
       }

Now, the error has solved.

Conclusion:

Those are two possible ways to solve this problem. Hope you have understood them.